1 /* 2 * llc_output.c - LLC minimal output path 3 * 4 * Copyright (c) 1997 by Procom Technology, Inc. 5 * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br> 6 * 7 * This program can be redistributed or modified under the terms of the 8 * GNU General Public License version 2 as published by the Free Software 9 * Foundation. 10 * This program is distributed without any warranty or implied warranty 11 * of merchantability or fitness for a particular purpose. 12 * 13 * See the GNU General Public License version 2 for more details. 14 */ 15 16 #include <linux/if_arp.h> 17 #include <linux/if_tr.h> 18 #include <linux/netdevice.h> 19 #include <linux/trdevice.h> 20 #include <linux/skbuff.h> 21 #include <net/llc.h> 22 #include <net/llc_pdu.h> 23 24 /** 25 * llc_mac_hdr_init - fills MAC header fields 26 * @skb: Address of the frame to initialize its MAC header 27 * @sa: The MAC source address 28 * @da: The MAC destination address 29 * 30 * Fills MAC header fields, depending on MAC type. Returns 0, If MAC type 31 * is a valid type and initialization completes correctly 1, otherwise. 32 */ 33 int llc_mac_hdr_init(struct sk_buff *skb, 34 const unsigned char *sa, const unsigned char *da) 35 { 36 int rc = 0; 37 38 switch (skb->dev->type) { 39 #ifdef CONFIG_TR 40 case ARPHRD_IEEE802_TR: { 41 struct net_device *dev = skb->dev; 42 struct trh_hdr *trh; 43 44 skb_push(skb, sizeof(*trh)); 45 skb_reset_mac_header(skb); 46 trh = tr_hdr(skb); 47 trh->ac = AC; 48 trh->fc = LLC_FRAME; 49 if (sa) 50 memcpy(trh->saddr, sa, dev->addr_len); 51 else 52 memset(trh->saddr, 0, dev->addr_len); 53 if (da) { 54 memcpy(trh->daddr, da, dev->addr_len); 55 tr_source_route(skb, trh, dev); 56 skb_reset_mac_header(skb); 57 } 58 break; 59 } 60 #endif 61 case ARPHRD_ETHER: 62 case ARPHRD_LOOPBACK: { 63 unsigned short len = skb->len; 64 struct ethhdr *eth; 65 66 skb_push(skb, sizeof(*eth)); 67 skb_reset_mac_header(skb); 68 eth = eth_hdr(skb); 69 eth->h_proto = htons(len); 70 memcpy(eth->h_dest, da, ETH_ALEN); 71 memcpy(eth->h_source, sa, ETH_ALEN); 72 break; 73 } 74 default: 75 printk(KERN_WARNING "device type not supported: %d\n", 76 skb->dev->type); 77 rc = -EINVAL; 78 } 79 return rc; 80 } 81 82 /** 83 * llc_build_and_send_ui_pkt - unitdata request interface for upper layers 84 * @sap: sap to use 85 * @skb: packet to send 86 * @dmac: destination mac address 87 * @dsap: destination sap 88 * 89 * Upper layers calls this function when upper layer wants to send data 90 * using connection-less mode communication (UI pdu). 91 * 92 * Accept data frame from network layer to be sent using connection- 93 * less mode communication; timeout/retries handled by network layer; 94 * package primitive as an event and send to SAP event handler 95 */ 96 int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb, 97 unsigned char *dmac, unsigned char dsap) 98 { 99 int rc; 100 llc_pdu_header_init(skb, LLC_PDU_TYPE_U, sap->laddr.lsap, 101 dsap, LLC_PDU_CMD); 102 llc_pdu_init_as_ui_cmd(skb); 103 rc = llc_mac_hdr_init(skb, skb->dev->dev_addr, dmac); 104 if (likely(!rc)) 105 rc = dev_queue_xmit(skb); 106 return rc; 107 } 108 109 EXPORT_SYMBOL(llc_mac_hdr_init); 110 EXPORT_SYMBOL(llc_build_and_send_ui_pkt); 111